Patent GB-1274582-A (GB)
Title: Improvements relating to apparatus for dressing grinding wheels
IPC: B24B53/07
Filed: 1970-01-09
Abstract: 1,274,582. Dressing grinding wheels. GLEASON WORKS. 9 Jan., 1970 [3 March, 1969], No. 1188/70. Heading B3D. Apparatus for dressing grinding wheels comprises first and second rotary dresser units 112, 114, Fig. 2, which function as a pair of dressers for simultaneously dressing inner and outer side wall portions 113, 115 of a cup-shaped grinding wheel 100, the units having axes of rotation parallel to each other and to the axis of rotation of the wheel when the dressers are in dressing contact with the wheels, and motor means for rotating the dresser units. The apparatus may be mounted in a machine in which the grinding wheel 100, Fig: 1, is carried by a vertically movable head 102 for grinding a gear or clutch member 104, the apparatus consisting of a bracket 106 movable about a pivot 108 by an hydraulic ram 110 between an inoperative position, as shown, and an operative position, shown dotted. A third rotary dresser unit 116 is mounted on the bracket for dressing the annular edge 130 of the grinding wheel. The dresser units 112, 114 are in the form of wheels which are mounted on a bracket 134 with axes on a common radius 128 of the grinding wheel, the wheel 112 being adjustable transversely on the bracket to adjust the spacing between the wheels. The bracket 134 is vertically adjustable on a mount 143 which in turn is adjustable about an axis 158, which passes through the axis 126 of the grinding wheel, on a block 152. The latter is adjustable about an axis passing through the imaginary apex point 130 of the grinding wheel at the point of dressing along arcuate guides on a mounting block 154 which is, in turn, adjustable in the direction of the radius 128 and up and down on a casing 146. The adjustments permit variations of the distance between the wheels, adjustment of the wheels from the axis of the grinding wheel, adjustment to position the wheels up or down the side walls of the grinding wheel, tilting the axis of the wheels for changing the pressure angle formed on the side walls of the wheel, and tilting about a further axis for modifying the tooth profile formed by the grinding wheel. The dressing wheels 112, 114 are shaped and preferably covered with diamond particles. The wheels are rotated by belt drive 184, Fig. 5, from a motor 118, the wheels rotating in the same direction but being reversible and driven at variable speed by the motor for effecting rough and fine dressing of the grinding wheel. The third rotary dresser unit for dressing the annular edge of the grinding wheel consists of a dressing wheel 116 which is driven by a motor 120. The wheel is disposed with its axis on a radius of the grinding preferably at 36 degrees to the radius 128. The motor is carried on a housing 306, Fig. 1, pivotally adjustable on a base block 308 which is adjustably received on a guide way 302 of a plate 300 formed on the casing 146. The tilting is effected by an hydraulically operated piston and controls the depth of dressing by the wheel 116. When used to dress a grinding wheel used in high speed grinding operations, the grinding wheel or the dressing tools may be moved relative to one another to form the grinding surfaces of the wheel with grooves 400, 402, Fig. 21, which permit a greater quantity of cooling fluid to flow to the grinding area. The apparatus may be used to dress a cup-shaped wheel rotating about a horizontal axis or be used to dress disc-shaped wheels.